Oct 9 posts of RobRoy and Stamps4Life.
About the "Horse & Dragon" issue.
Its not my "conclusion", but general knowledge in real stamp catalogs.
And China stamp collectors, specialized catalogs like Chan or CSS.
The two reference stamps shown on the stampworld site are also forgeries The red one has a fantasy marking:


For modern issues, its great to have an illustrated freebie site like stampword,.
But they should be used with caution regarding classic issues. Did a test with old Japan known for fakes. Their Japan stamp pictures #1/35 includes 9 forgeries.
Old Formosa/Taiwan, suggest to look it up in real stamp catalog like SG or Michel. The overprinted/surcharged versions are in SG.
Here is what the Taiwan Postal Museum says about the genuine ones:
https://museum.post.gov.tw/post/Pos...B0366FF81106For current pictorial reference. A group of "Horse & Dragon" stamps unused mint in final colours as well as colour proofs and ovpt. issues inc. useds was sold past week October 14 at the german CG auction.
Lots #2607/2618, click pics for enlarged views:
https://www.auktionen-gaertner.de/e...D_AT_AUCTION